Better immunity in later life: a position paper

Ageing is the greatest challenge that health-care systems will have to deal with this century. This is because a wide spectrum of pathological impairments emerge in the later part of the human life course which sharply increase mortality and reduce quality of life. Dysfunction of the immune system with advancing age is of crucial importance to the development of disability in later life and finally death. Understanding immune ageing, immunosenescence, has long been recognised as an essential prerequisite for the delivery of effective interventions which will improve late life health. Ten years ago, the ImAginE consortium undertook a broad ranging series of projects which added significantly to our understanding of how fundamental ageing mechanisms drove immune decline. In the decade which followed, abundant evidence has accumulated from nonhuman model systems that ageing results from the progressive operation of a relatively few common processes which act across the major organ systems. These advances in fundamental understanding both allow better clarification of the potential cross-system dysregulation that occurs in ageing and open new avenues for intervention. Over the course of a 2-day workshop, the original ImAginE participants have considered these issues and present some suggestions for current priority areas in immunosenescence.     

黄芪建中汤肠内灌注对抗生素相关性腹泻患者肠道菌群、粘膜功能及炎性因子表达的影响

背景临床对抗生素相关性腹泻(antibiotic-associated diarrhea,AAD)尚无特效疗法,一般采用支持治疗与重建正常菌群-微生物制剂,但疗效不理想.黄芪建中汤源自张仲景《金匮要略》,为温阳健脾代表方,具有和胃止痛、温中健脾等功效.目的分析黄芪建中汤肠内灌注对抗生素相关性腹泻患者肠道菌群结构、肠粘膜功能损伤及炎性因子表达的影响.方法选取2016-12/2018-12于本院接受治疗的脾胃虚寒型AAD患者148例,随机数字表法将患者分成2组,分别为对照组(74例)口服双歧杆菌四联活菌片,观察组(74例)在对照组基础上采用黄芪建中汤肠内灌注.观察患者临床疗效、血清炎性因子含量、T淋巴细胞亚群、肠道菌群结构及肠粘膜屏障功能改善情况.结果观察组患者总有效率为94.59%,高于对照组79.73%,差异有统计学意义(P<0.05);治疗后2组患者血清白细胞介素-6(interleukin-6,IL-6)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、降钙素原(procalcitonin,PCT)及C反应蛋白(C-reactive protein,CRP)含量较治疗前降低,且观察组血清IL-6、TNF-α、PCT及CRP含量低于对照组,差异有统计学意义(P<0.05);治疗后2组患者粪便内双歧杆菌、肠杆菌及乳杆菌较治疗前升高,观察组粪便内双歧杆菌、肠杆菌及乳杆菌高于对照组,差异有统计学意义(P<0.05);治疗后2组患者血清细菌内毒素(endotoxin,BT)、D-乳酸(D-lactic acid,D-LC)及二胺氧化酶(diamine oxidase,DAO)含量较治疗前降低,观察组患者血清BT、D-LC及DAO含量低于对照组,差异有统计学意义(P<0.05).结论黄芪建中汤肠内灌注治疗AAD有效率高于双歧杆菌四联活菌片,能够可降低AAD患者血清炎性因子水平,加强机体免疫力,改善患者肠粘膜屏障功能与肠道菌群结构.     

桂枝茯苓丸对大鼠卵巢癌移植瘤的抑瘤作用及其机制

目的 探讨桂枝茯苓丸对大鼠卵巢癌移植瘤的抑瘤作用及其机制。方法 将30只SD雄性大鼠随机分为对照组、模型组和桂枝茯苓丸组,每组10只。模型组和桂枝茯苓丸组皮下接种人卵巢癌HO 8910细胞,建立裸鼠卵巢癌移植瘤模型。造模成功后,桂枝茯苓丸组灌胃桂枝茯苓丸组方,连续灌胃10d,对照组和模型组大鼠灌胃等体积的蒸馏水。治疗后,检测卵巢癌移植瘤的体积和重量,测定大鼠血清卵泡刺激素（FSH）、促黄体生成素（LH）、血清糖链蛋白（CA）125、白介素（IL）-2和IL-6水平,荧光定量PCR和Western Blot检测卵巢癌移植瘤组织中半胱氨酸蛋白酶（Caspase-3）、存活蛋白（survivin）和p21waf/cip蛋白和mRNA的表达。结果 与模型组比较,桂枝茯苓丸组卵巢癌移植瘤的体积和重量显著减小,血清IL 2的水平显著升高,血清FSH、LH、CA125、IL 6的水平显著降低,survivin的蛋白和mRNA表达量显著下降,Caspase-3和p21waf/cip的蛋白和mRNA表达量显著升高（均P＜0.05）。结论 桂枝茯苓丸可以增强机体免疫力,促进肿瘤细胞的凋亡,从而达到抗肿瘤的作用。     

Analysis of T Cell Receptor Vβ Diversity in Peripheral CD4+ and CD8+ T Lymphocytes Obtained From Patients With Chronic Severe Hepatitis B

Background:

The hepatitis B virus (HBV) antigen-induced cellular immune response plays an important role in HBV clearance. Changes in the diversity of complementarity determining region 3 (CDR3) and T-cell receptor (TCR) sequences are used to monitor the response of T cells to antigens.

Objectives:

The aim of the present study was to determine whether the TCR Vβ repertoire of patients with chronic severe hepatitis B (CSHB) undergoes increased stimulation, and to identify conserved motifs in specific TCR Vβ families.

Patients and Methods:

Peripheral blood mononuclear cells (PBMCs) from 18 patients with CSHB were sorted into CD4+ and CD8+ T subsets, using monoclonal antibody-coated magnetic beads. The TCR Vβ CDR3 was subsequently characterized using immune spectratyping. The TCR Vβ families exhibiting a CDR3 spectratype that underwent monoclonal expansion were sequenced.

Results:

The number of oligoclonal or monoclonal expansion TCR Vβ families detected in the analyzed CD8+ T cells was significantly higher than the number detected in CD4+ T cells. The CDR3 spectratype analysis showed predominant usage of TCR Vβ5, Vβ7, Vβ9, Vβ12, and Vβ18 families in CD8+ T cell subsets of CSHB patients. Furthermore, conserved amino acid motifs were found to be associated with the monoclonal expansion of CD8+ TCR Vβ families. In addition, JB1S1 and JB2S7 region genes were present at a high frequency.

Conclusions:

The CD4+ and CD8+ TCR Vβ gene families undergo clonal expansion in CSHB patients, and CD8+ T cells play a major role in the pathogenesis of CSHB. Moreover, the conserved motifs and limited use of joining region genes observed in the CSHB patients of this cohort indicated that similar antigenic epitopes are recognized.     

血清25-羟维生素D水平与儿童免疫功能和反复呼吸道感染的关联性分析

背景　高水平的25-羟维生素D〔25（OH）D〕维持着人体骨骼系统外细胞25（OH）D受体的正常新陈代谢,与血液循环系统、呼吸系统、结缔组织及自身免疫疾病和肿瘤的发展密切相关,相关研究表明,每天补充4 000 U的25（OH）D3可显著减少免疫缺陷患儿的感染症状、鼻拭子中的致病菌数量、对抗生素的消耗,减少儿童由于免疫功能不完善导致反复呼吸道感染的发生。目的　对反复呼吸道感染儿童的血清25（OH）D水平在不同IgG和IgM水平患儿中的分布差异及与乙肝抗体（anti-HBs）滴度和反复呼吸道感染次数之间的关联性进行分析,为25（OH）D补充剂在减少儿童反复呼吸道感染中的实际应用提供线索。方法　选取2016年8月-2018年10月于安徽医科大学第一附属医院接受治疗的反复呼吸道感染患儿146例,根据年龄分为0~<2岁组、2~<6岁组、6~<12岁组、12~16岁组,比较各年龄组血清25（OH）D水平;根据研究对象的血清IgG、IgM水平分为IgG降低组79例、IgG正常组38例及IgG升高组30例,IgM降低组92例、IgM正常组29例及IgM升高组25例,比较各组间血清25（OH）D水平;采用泊松回归分析对血清25（OH）D水平与儿童反复呼吸道感染次数进行关联性分析。结果　0~<2岁组血清25（OH）D水平高于2~<6岁组、6~<12岁组和12~16岁组（q=5.202、6.030、8.432,P值均<0.001）;2~<6岁组和6~<12岁组血清25（OH）D水平高于12~16岁儿童（q=5.317、5.559,P值均<0.05）。泊松回归分析结果显示,血清25（OH）D水平与儿童反复呼吸道感染次数呈现负向关联〔FR=0.94,95%CI（0.89,1.02）,P=0.048〕。结论　儿童的血清25（OH）D水平与血清anti-HBs滴度无相关关系,与反复呼吸道感染次数呈现负向关联。     

新冠病毒疫苗研发的思路与前景

随着中国新冠病毒疫情的缓解,全国各地逐步进入一个低传播或无传播阶段。尽管局部和零星的疫情爆发依旧是一个实际存在的可能,但是通过前期抗疫中积累的医疗和流行性疾病管理经验,以及全国上下对这类病毒流行的高度警惕和防备,目前和未来可能的疫情变化应该是“可防可控”的。根据国内外专家的预测新型冠状病毒极有可能将长期与人类共存并将呈现季节性或不定期的复发,因此建立人群对于新冠病毒的免疫力是一个关键性和根本性的防御措施。目前世界各国都在积极研发针对这次新冠病毒的疫苗,以期通过普遍接种疫苗达到有效“群体免疫”。本文介绍了目前几类主要的疫苗研发技术平台,并对于不同技术平台和产品的优势和劣势进行了初步的比较和分析,为正在与时间竞赛,积极开展新冠疫苗的研究人员提供一些建议和思路。     

肠三叶因子对肠黏膜保护与修复的研究

肠三叶因子（ITF）由杯状细胞合成和分泌,是肠道的特异性保护因子,通过与黏蛋白的结合、抑制免疫反应和调节凋亡来保护肠黏膜。ITF对维持肠黏膜的完整性、促进肠黏膜损伤后重建和修复具有重要作用。本文就ITF对肠黏膜保护与修复的研究作一综述。     

肿瘤坏死因子-α诱导蛋白-8样分子2对小鼠调节性T细胞免疫调节功能的影响

目的 观察肿瘤坏死因子-α诱导蛋白-8样分子2(tumor necrosis factor -αinduced protein 8 like -2,TIPE2)在CD4+ CD25+调节性T细胞(CD4+ CD25 +Treg细胞)中的表达,并进一步分析其对CD4+ CD25+ Treg细胞免疫抑制活性的影响. 方法 免疫磁珠法分选正常BALB/c小鼠脾脏CD4+ CD25+ Treg细胞.采用RT - PCR和Western blot技术分别从mRNA和蛋白水平检测CD4+ CD25+ Treg细胞细胞内TIPE2表达.进一步应用小RNA干扰技术(siRNA)沉默TIPE2表达,流式细胞术观察TIPE2对T淋巴细胞毒性相关抗原(CTLA) -4及叉头翼状螺旋转录因子(Foxp3)表达的影响,ELISA法检测CD4+ CD25+ Treg细胞分泌IL - 10和转化生长因子(TGF)-β水平,并通过MTT比色试验观察效应T细胞增殖活性的改变. 结果 RT - PCR分析在CD4+CD25+ Treg细胞中检测到147 bp大小的特异性TIPE2目的基因条带.Western blot检测证实CD4+CD25+ Treg细胞中存在清楚的TIPE2条带,相对分子质量为21 000.siRNA处理CD4+ CD25+ Treg细胞后,经抗CD3/CD28刺激活化的CD4+ CD25+ Treg细胞培养24h时CTLA -4和Foxp3表达明显下降(P＜0.01),同时IL - 10和TGF -β生成量显著减少(P＜0.01);此外,CD4+ CD25+Treg细胞对CD4+ CD25 -T细胞的抑制功能明显减弱(P＜0.05). 结论 TIPE2作为一种重要的负向调控分子,在CD4+ CD25+ Treg细胞中表达并影响CD4+ CD25+ Treg细胞的免疫抑制功能.